Grapple for handling logs or the like



Dec. 8, 1959 A. R. WIRKKALA 2,9 6,3

GRAPPLE FOR HANDLING LOGS OR THE LIKE Filed Jan. 20, 1958 United States Patent 2,916,322- GRAPPLE FOR HANDLING LOGS 0R ma LIKE Albert R. Wirkkala, Naselle, Wash. Application January '20, 1958, Serial No. 709,884

'1 Claim. 01. 294-112 This invention relates to improvements in grapples, and has reference more particularly to what are designated or known in the logging industry as log grapples, and which generally are used in connection with a boom for [the picking up and moving of a plurality of logs at a time, or for the handling of other elongated objects of a like character such as beams or rails.

It is the primary object of this invention to provide a grapple of the above stated character that is relatively light in weight; that is of substantially lesser height than grapples now generally in use for the same purpose; that has a comparatively simple and effective mechanism for opening and closing the grapple, and which is operated between open and closed condition through the mediacy of the cables whereby it is suspended from the boom.

Further objects and advantages of the present invention reside in the details of construction and combination of parts embodied therein and in their mode of operation, as will hereinafter be fully described.

In accomplishing these and other objects, I have provided the improved details of construction, the preferred forms of which are illustrated in the accompanying drawings, wherein:

Fig. 1 is a perspective view of a grapple embodying the improvements of the present invention therein; the grapple being shown in open condition, as for receiving a load.

Fig. 2 is an end view of the grapple shown in closed condition.

Fig. 3 is a vertical section taken substantially on the line 3-3 in Fig. 2 illustrating certain details of construction.

Referring more in detail to the drawings:

In itspresent preferred form, as for the handling of logs or the like, the grapple comprises three coacting tines or tongs. As seen best in Fig. 1, two of these tongs, designated respectively by reference numerals and 10', have their inner end or head portions, 10k and 10h, fixedly mounted on the opposite end portions of two parallel cross-shafts 11 and 12. Pivotally mounted on the crossshaft 12, midway between its ends is the third tong which is herein designated by reference numeral 10x. All tongs, 10, 10' and 10x are of the same size and of substantially semi-circular curvature, and each is of strong, rigid construction. The tong 10x is opposedly faced with reference to the tongs 10 and 10' and it coacts therewith, when the grapple is closed as in Fig. 2, to provide a closed sling in which elongated objects such as logs, rails, beams, or the like, represented in dash lines at 13, may be held for conveyance.

It will be understood that the coacting tongs, 10-10' at one side, and tong 10x at the other side, swing between their closed relationship, as seen in full lines in Fig. 2, to their open relationship as seen in dash lines, about the cross-shaft 12 as a turning axis. The means whereby the opening and closing actions of the tongs are effected is as follows: Pivotally fixed to the head portion 10h of tong 10x outwardly from the shaft 12 is a lever 15,

wardly from the outer end of the boom, not herein shown, from which the grapple is suspended.

Pivotally attached to the cross-shaft 11, near the.

laterally spaced head portions of the tongs 10-10', are paired links 20-20, which, at their upper ends are pivoted by a bolt 21 to the hanger lever 15 between its ends. The hanger lever 15 and the links 20-20, as thus joined together, provide a toggle linkage whereby the opposedly related tongs can be caused to be adjusted between open and closed relationship.

In the event that the tongs are held in suspension by the cable 18 as in Fig. 1, the toggle linkage assumes that relationship to the tongs in which it is best shown in dash lines in Fig. 2. In their opening, the tongs swing pivotally away from each other on shaft 12. When held in this open position by means of the cable 18, the tongs may be lowered, or moved to a load pick up position, by the boom. After they have been properly located for picking up a load, they are caused to be closed together to gather in and secure the load as indicated in Fig. 2.

The closing of the coacting tongs is effected by the second cable, which is herein designated by numeral 20. This extends downwardly from the boom end, about a sheave wheel 25 that is mounted for rotation on crossshaft 12 medially of its ends, thence upwardly, and is attached at its end to the outer end of the hanger lever 15. When it is desired to close the tongs, the cable 18 is slacked off, and the cable 20 is wound in. This causes the toggle linkage to be adjusted from the dotted line position toward the straightened position of Fig. 2; this being due to the downward pull by cable 20 on the outer end of lever 15, and upward pull on shaft 12. The grapple upon being closed can then be carried by the boom to a place of disposition of the load. When the load is to be dumped, the pull on cable 20 is slacked off as upward pull on cable 18 is resumed. This returns the tongs to the open position where they will remain as long the the grapple is held suspended by cable 18.

To prevent wear on the cables, it is desirable to apply rotatable sleeves 30 about the pivot bolt 21, between the spaced side members of lever 15, and about the cross-shaft 11 between the levers 20-20. These sleeves rotate freely when contracted by the taut cables and thus reduce frictional wear thereon to a minimum.

Grapples of this kind may be made with one or more tongs on each side, and the tongs may be of the curved form here shown or of any other suitable form. The shape and proportionate dimensions of parts and details of construction may be changed within reasonable limits without departing from the spirit of the invention.

The principal advantages of this form of grapple reside in its relatively light weight; its few parts, its cable operation; the simplicity of its operating linkage and the fact that it has no disadvantageous height or bulky upper structure. It can be easily handled by the two suspending cables from the usual type of boom and used after the fashion of the tongs which have been illustrated in US. patent to Carlson, issued under No. 2,327,015.

What I claim as new is:

A grapple of the character described comprising opposed, cooperatively arranged tongs, one end of each said tongs including head portions pivotally mounted on a cross-shaft, a toggle including a link and a lever disposed above and transversely of said cross-shaft, the link having an inner end and upper end and said lever having a lower end and an outer end, the inner end of said link being pivotally joined to the head portion of one of said tongs at a point outside, the mounting of the tong on said cross-shaft and the upper end of the link being pivotally connected to said lever intermediate its ends, the lower end of the lever being pivotally joined to the head portion of the other tong at. a point outside the mounting of the tong on said cross-shaft, a sheave rotatably mounted on said cross-shaft, a grapple closing and, lifting cable attached to the outer end of said lever and extended, downwardly therefrom, about said sheave wheel and thence upwardly to a loading boom or the like, and a grapple opening cable attached to the outer end of said lever and extended directly upward to the loading boom.

References Cited in 4', v the file of this patent UNITED STATES PATENTS Niedermier May 7, 1907 Erickson June 21, 1910 Jones July 2. 1912 Tornquist Nov. 18, 1930 Collom eral. Sept. 29, 1931 Bartlett July 18, 1.9.39 Kamppi Apr. 14, 1942 Hall Nov. 7, 1944 Billings Ma); 26, 1953 

